C Program to create a Menu Driven software using Switch Case

Below is a menu driven program using switch case.

unsigned is doubled the size of signed as it only considers positive values.

%lu is the format specifier for unsigned integer.

A number divisible by an integer other than 1 and itself is called a composite number.

#include<stdio.h> int main() { printf("\n\n\t\tStudytonight - Best place to learn\n\n\n"); int choice, num, i; unsigned long int fact; while(1) { printf("1. Factorial \n"); printf("2. Prime\n"); printf("3. Odd\\Even\n"); printf("4. Exit\n\n\n"); printf("Enter your choice : "); scanf("%d",&choice); switch(choice) { case 1: printf("Enter number:\n"); scanf("%d", &num); fact = 1; for(i = 1; i <= num; i++) { fact = fact*i; } printf("\n\nFactorial value of %d is = %lu\n\n\n",num,fact); break; case 2: printf("Enter number:\n"); scanf("%d", &num); if(num == 1) printf("\n1 is neither prime nor composite\n\n"); for(i = 2; i < num; i++) { if(num%i == 0) { printf("\n%d is not a prime number\n\n", num); break; } } /* Not divisible by any number other than 1 and itself */ if(i == num) { printf("\n\n%d is a Prime number\n\n", num); break; } case 3: printf("Enter number:\n"); scanf("%d", &num); if(num%2 == 0) // 0 is considered to be an even number printf("\n\n%d is an Even number\n\n",num); else printf("\n\n%d is an Odd number\n\n",num); break; case 4: printf("\n\n\t\t\tCoding is Fun !\n\n\n"); exit(0); // terminates the complete program execution } } printf("\n\n\t\t\tCoding is Fun !\n\n\n"); return 0; }

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